The Company leases facilities and certain equipment under noncancelable operating leases with remaining lease terms of 0.8 years to 10.2 years, some of which include options to extend for up to two five-year terms. These optional periods were not considered in the determination of the right-of-use asset or the lease liability as the Company did not consider it reasonably certain that it would exercise such options.

	Three Months Ended March 31,
	2021		2020
Operating lease cost	$	2,378	$	1,487

Supplemental cash flow information related to the Company’s leases were as follows (in thousands):

	Three Months Ended March 31,
	2021		2020
Cash paid for amounts included in the measurement of lease liabilities:
Operating cash flows from operating leases	$	1,014	$	1,291
Right-of-use assets obtained in exchange for operating lease obligations:		17,417		276

The balance sheet classification of the Company’s lease liabilities was as follows (in thousands):

	March 31, 2021		December 31, 2020
Operating lease liabilities
Current portion included in accrued liabilities	$	6,082	$	5,087
Operating lease liabilities		60,581		44,460
Total operating lease liabilities	$	66,663	$	49,547

	Operating Leases
Remainder of 2021	$	4,071
Years ending December 31,
2022		8,739
2023		8,506
2024		8,275
2025		8,355
Thereafter		44,276
Total lease payments		82,222
Less:
Imputed interest		(15,559	)
Total operating lease liabilities	$	66,663

Operating lease liabilities are based on the net present value of the remaining lease payments over the remaining lease term. In determining the present value of lease payments, the Company uses its incremental borrowing rate based on the information available at the lease commencement date. As of March 31, 2021, the weighted average remaining lease term was 9.6 years and the weighted average discount rate used to determine the operating lease liability was 4.4%.

In the fourth quarter of 2018, the Company entered into an agreement to lease the 4^th and 5^th floors of corporate office space in San Diego, California with total minimum lease payments of $50.4 million over an initial term of 10 years and 9 months. In February 2020, the Company entered into the first amendment to the lease agreement to lease the 2^nd floor of corporate office space in San Diego, California with total minimum lease payments of $25.3 million over an initial term of approximately 10 years and 7 months. In March 2020, the Company entered into the second amendment to the lease agreement which increased the total minimum lease payments of the original corporate office space to $51.4 million. In the third quarter of 2020, the lease for the 4^th and 5^th floors of corporate office space commenced and the Company capitalized a right of use asset and related lease liability of $40.3 million. During the three months ended March 31, 2021, the lease for the 2^nd floor of corporate office space commenced and the Company capitalized a right of use asset and related lease liability of $19.2 million. In connection with this lease and the amendment, the Company established a letter of credit for $3.1 million, which has automatic annual extensions and is fully secured by restricted cash.